Knob



FIG. 1 is a front right perspective view of a knob according to my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a right side view thereof; and,

FIG. 4 is a front right perspective view thereof shown in environmental use.

The views of the knob not shown form no part of the claimed design. The broken lines shown represent unclaimed subject matter and form no part of the claimed design. 

CLAIM I claim the ornamental design for a knob, as shown and described. 